1. Field of the Invention
This invention relates to metallic channels used in various types of construction and, more particularly, to an improved configuration which reduces the thermal conductivity between said channels and adjacent materials.
2. Discussion of Prior Art
Metal channels are commonly used as components in many types of built assemblies. Currently, one of the primary problems associated with the use of these metal channels as framing members involves their high level of thermal transmission due to conductivity. In these built assemblies a thermal bridge is created by the metal channels through which heat may be transferred. The transfer of heat across this thermal bridge in turn manifests itself in the form of increased energy consumption. A number of attempts to solve this problem have been proposed; however, all of these prior proposals present significant disadvantages that severely limit and in some cases eliminate their practical application and use.
For example, U.S. Pat. No. 5,235,054 to Gilmour describes a thermal metallic building stud which attempts to limit contact between the metal framing member and adjacent materials via an upset pattern of punched protuberances which are pushed from the interior surfaces outwardly and cover the length and width of the stud flange. These punched projections present two significant problems: one involving the common use of mechanical fastening devices in conjuction with metal framing and one regarding the industry standardized structural widths currently used for metal framing members. Firstly, the distribution of projections across the width of the flange and away from the web serves as an obstruction to commonly used fasteners such as screws or nails. When hit, these protrusions can cause those fasteners to deflect and bend, as illustrated in FIGS. 4 and 5. Secondly, unless the total structural depth of the stud is reduced accordingly, whereby its load beating capacity is altered, the increased dimension resulting from the outwardly struck protuberances will hinder the use of the described thermal metallic building stud within standardized systems of metal runners and aim channels.
As a result, a need currently exists for thermally-improved metallic channels which possess characteristics not exhibited by the prior art. These specific characteristics are designated as the objects and advantages of the invention described herein.